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Diffusion and advection with sorption of anions, cations and non-polar molecules in organo-clays at varying thermo-chemical conditions - validation by analytical methods and molecular simulation

The sorption of anions in geotechnical multibarrier systems of planned high level waste repositories (HLWR) and of non-ionic and organic pollutants in conventional waste disposals are in the center of recent research. In aquatic systems, persistent radionuclides such as 79Se, 99Tc, 129I exist in a form of anions. There is strongly increasing need to find materials with high sorption capacities for such pollutants. Specific requirements on barrier materials are long-term stability of adsorbent under various conditions such as T > 100 C, varying hydrostatic pressure, and the presence of competing ions. Organo-clays are capable to sorb high amounts of cations, anions and non-polar molecules simultaneously having selectivity for certain ions. This project is proposed to improve the understanding of sorption and desorption processes in organo-clays. Additionally, the modification of material properties under varying chemical and thermal conditions will be determined by performing diffusion and advection experiments. Changes by sorption and diffusion will be analyzed by determining surface charge and contact angles. Molecular simulations on models of organo-clays will be conducted in an accord with experiments with aim to understand and analyze experimental results. The computational part of the project will profit from the collaboration of German partner with the group in Vienna, which has a long standing experience in a modeling of clay minerals.

Evaluating current European agri-environment schemes to quantify and improve nature conservation efforts in agricultural landscapes (EASY)

Research question: Agri-environment schemes play an increasingly important role in European CAP (Common Agricultural Policy) to support biodiversity and environment in agricultural landscapes. They have been implemented since 1992 and now cost a yearly 1.7 billion Euro. Still, there is no conclusive evidence that these schemes actually do contribute to the conservation of particularly biodiversity. The primary objective of this project is to evaluate the (cost-) effectiveness of European agri-environment schemes in protecting biodiversity and to determine the primary processes that determine their effectiveness. This project furthermore aims to determine how CAP may be introduced in candidate EU-members without unacceptable loss of biodiversity. It will provide simple guidelines how researchers, governmental authorities may efficiently evaluate agri-environmental measures. Aim: Agri-environment schemes have been used to protect biodiversity and environment in agricultural areas since 1992. Their effectiveness has never been reliably evaluated. This project aims to evaluate the (cost-)effectiveness of agri-environment schemes with respect to biodiversity conservation in five European countries. It will determine the proper scales that have to be addressed for conservation efforts for a range of species groups. It will determine the most important environmental factors that influence the effectiveness of the schemes. Based on this, recommendations will be made how the effectiveness of schemes may be improved and simple guidelines will be produced how ecological effects of agri-environment schemes can be evaluated efficiently by governmental authorities or other institutions. The ecological effects of the introduction of CAP in a candidate EU-member will be investigated to reduce negative side effects of anticipated land-use changes Scientific methods: We will examine the effectiveness of agri-environment schemes by surveying pairs of fields: a field with an agri-environment scheme and a nearby field that is conventionally managed. In five countries, in each country in three areas, and in each area on seven pairs of fields the species richness of birds, plants and three insect groups (pollinators, herbivores, predators) will be determined. Effects of schemes on pollination efficiency and pest control will be examined using indicator communities. Correlative studies will examine the effects of landscape structure, land-use intensity and species pool on the effectiveness of agri-environmental measures. The spatial scale that is relevant to nature conservation efforts will be investigated via the spatial distribution of species groups. The results will be used to formulate recommendations how to improve the effectiveness of agri-environment schemes and to construct a set of simple guidelines how schemes can be evaluated efficiently yet reliably.

Schwerpunktprogramm (SPP) 1488: Planetary Magnetism (PlanetMag), Probing the Earth's subdecadal core-mantle dynamics based on satellite geomagnetic field models

The CHAMP mission provided a great amount of geomagnetic data all over the globe from 2000 to 2010. Its dense data coverage has allowed us to build GRIMM - GFZ Reference Internal Magnetic Model - which has the highest ever resolution for the core field in both space and time. We have already modeled the fluid flow in the Earth's outer core by applying the diffusionless magnetic induction equation to the latest version of GRIMM, to find that the flow evolves on subdecadal timescales, with a remarkable correlation to the observed fluctuation of Earth rotation. These flow models corroborated the presence of six-year torsional oscillations in the outer core fluid. Torsional oscillation (TO) is a type of hydromagnetic wave, theoretically considered to form the most important element of decadal or subdecadal core dynamics. It consists of relative azimuthal rotations of rigid fluid annuli coaxial with the mantle's rotation and dynamically coupled with the mantle and inner core. In preceding works, the TOs have been studied by numerical simulations, either with full numerical dynamos, or solving eigenvalue problems ideally representing the TO system. While these studies drew insights about dynamical aspects of the modeled TOs, they did not directly take into account the observations of geomagnetic field and Earth rotation. Particularly, there have been no observation-based studies for the TO using satellite magnetic data or models. In the proposed project, we aim at revealing the subdecadal dynamics and energetics of the Earth's core-mantle system on the basis of satellite magnetic observations. To that end, we will carry out four work packages (1) to (4), for all of which we use GRIMM. (1) We perform timeseries analyses of core field and flow models, to carefully extract the signals from TOs at different latitudes. (2) We refine the conventional flow modeling scheme by parameterizing the magnetic diffusion at the core surface. Here, the diffusion term is reinstated in the magnetic induction equation, which is dynamically constrained by relating it to the Lorentz term in the Navier-stokes equation. (3) We develop a method to compute the electromagnetic core-mantle coupling torque on the core fluid annuli, whereby the energy dissipation due to the Joule heating is evaluated for each annulus. This analysis would provide insights on whether the Earth's TOs are free or forced oscillations. (4) Bringing together physical implications and computational tools obtained by (1) to (3), we finally construct a dynamical model for the Earth's TOs and core-mantle coupling such that they are consistent with GRIMM and Earth rotation observation. This modeling is unique in that the force balances concerning the TOs are investigated in time domain, as well as that the modeling also aims at improving the observation-based core flow model by considering the core dynamics.

Soil colour spectra of prehistoric pit fillings as a new analytical tool to measure changing soil characteristics over time on a regional scale

Prehistoric pits are filled with ancient topsoil material, which has been preserved there over millennia. A characteristic of these pit fillings is that their colour is different depending on the time the soil material was relocated. Soil colour is the result of soil forming processes and soil properties, and it could therefore indicate the soil characteristics present during that specific period. To the best of our knowledge, no investigation analysed and explained the reasons for these soil colour changes over time. The proposed project will investigate soil parameters from pit fillings of different archaeological periods in the loess area of the Lower Rhine Basin (NW-Germany). It aims to implement the measurement of colour spectra as a novel analytical tool for the rapid analyses of a high number of soil samples: the main goal is to relate highresolution colour data measured by a spectrophotometer to soil parameters that were analysed by conventional pedogenic methods and by mid infrared spectroscopy (MIRS), with a main focus on charred organic matter (BPCAs). This tool would enable us to quantify the variation of soil properties over a timescale of several millennia, during different prehistoric periods at regional scale and for loess soils in general. Detailed information concerning changing soil properties on a regional scale is necessary to determine past soil quality and it helps to increase our understanding of prehistoric soil cultivation practices. Furthermore, these information could also help to increase our understanding about agricultural systems in different archaeological periods.

Native plants and mycorrhizal fungi in wind erosion control in the Kailash-Manasarovar region (Tibet, China)

We study the effects of plants and root-associated fungi on wind erosion within the alpine environment of Tibet. China is one of the countries most affected by desertification processes and Tibet, in particular, a key region in desertification combat. The presented project focuses on the Barkha Plain surrounded by Mount Kailash and the Lake of Manasarovar (Ngari Prefecture). This Western Tibet region experienced little scientific attention but, nowadays, faces rapidly increasing touristic activities and expanding local settlements associated with socio-economic changes that are serious threats to the delicate ecological balance and potential triggers of desertification. It exists almost unanimous agreement that revegetation is the most efficient and promising strategy to combat wind erosion and desertification in the long term. However, re-colonising success is often poor, mainly under extreme environmental conditions. Compared to conventional practices, the approach of the presented project attains better accordance with natural succession processes and promises acceleration of both plant and soil development and, conclusively, more efficient desertification control. The project assesses the potential of native plants and symbiotic fungi to control wind erosion and desertification processes. It aims to identify key plants and fungi that increase soil aggregate stability and efficiently drive succession into a natural and self-maintaining cycle of the ecosystem. Furthermore, it provides crucial information for implementing environmentally compatible and cost-effective measures to protect high-elevation ecosystems against desertification. Within three successional stages (early, intermediate, late), field investigations are performed on the basis of Modified-Whittaker plots. Classic methods of vegetation analysis and myco-sociology are combined with analysis of distribution patterns at different scales (patchiness, connectivity). Comprehensive soil analysis is performed comprising grain size distribution, aggregate stability, pH as well as water and nutrient contents. Additionally, important parameters of wind erosion are measured concurrently and continuously to assess their magnitude and variability with respect to vegetation and soil at different levels of development. The parameters addressed, include sediment transport, air temperature, radiation, precipitation, relative humidity as well as speed and direction of wind. Surface moisture is recorded periodically and roughness described. Species and environmental parameters are checked for spatial correlation. Cutting edge technologies are applied in laboratory work, comprising molecular methods for fungal species identification and micro-tomography to analyse soil structure. Furthermore, successfully cultivated fungi and plants are subject of synthesis experiments and industrial propagation in view of practical implementation in restoration measures.

Schwerpunktprogramm (SPP) 1689: Climate Engineering: Risiken, Herausforderungen, Möglichkeiten?, Climate Engineering on Land: Potentials and side-effects of afforestation and biomass plantations as instruments for carbon extraction (CE-LAND WP5) Land use trade-offs in terrestrial CDR pathways

The objective of this project is to provide a comprehensive quantification of the potentials and consequences of large-scale terrestrial Carbon Dioxide removal (CDR) as a strategy for climate engineering (CE). Using two state-of-the-art modeling systems, MPI-ESM and LPJmL, we will quantify Carbon sequestration potentials of four different forest CDR types: semi-natural forest, managed forest and biomass plantation of woody and herbaceous plant types, for various biomass utilization pathways such as conventional wood usage or CCS. The analysis includes associated changes in ecosystem processes and surface properties and their effects on, and feedbacks to, local to global climate. We will additionally analyze (unintended) consequences of these different terrestrial CDR strategies vis-à-vis other prospective use of land and water resources, particularly for food production and ecosystem conservation, and identify regions where afforestation is judged to be sustainable from this broader perspective. WP 5 - Land use trade-offs in terrestrial CDR pathways.

Entwicklung eines Analyseverfahrens für Tenside aus Wasch- und Reinigungsmitteln und dessen praktische Anwendung auf Abwasserproben von Kläranlagenabläufen

Zur Bestimmung der Konzentrationen linearer Alkylbenzolsulfonate (LAS) und Alkylethersulfate (AES) in Kläranlagenabläufen wurden 7-Tagesmischproben (n=33) an Abläufe von 33 konventionellen Kläranlagen in Deutschland genommen. Zudem wurden an vier der untersuchten Kläranlagen die Zuläufe beprobt und ebenfalls auf LAS und AES untersucht, um Rückschlüsse auf die Entfernung dieser Tenside in konventionellen Kläranlagen ziehen zu können. Insgesamt umfasste die Studie die Analyse von vier LAS-Homologen (C10-C13) sowie von jeweils 10 Ethoxymeren zweier Homologe von AES (C12 und C14, jeweils mit 0-9 Ethoxygruppen). Die Probenvorbereitung bestand aus der Entfernung der wässrigen Phase mit Hilfe eines Rotations-Vakuum-Konzentrators und anschließender Resolvatisierung des Trockenrückstandes in einer definierten Menge Reinstwasser und Acetonitril. Die Identifikation und Quantifizierung der Zielanalyten erfolgte mittels Hochleistungsflüssigkeitschromatographie mit Tandem-Massenspektrometrie-Kopplung (HPLC-MS/MS). Die Leistungsfähigkeit der analytischen Methoden wurde in Leitungswasser und Kläranlagenablauf evaluiert. Die Analysemethoden zeigten für beide Matrices eine allgemein gute Richtigkeit sowie Präzision. Basierend auf den geschätzten mittleren Konzentrationen einzelner LAS-Homologe wurde eine mittlere Gesamtkonzentration von 14,4 Mikro g/L in Kläranlagenabläufen ermittelt. Verglichen mit LAS, wurden für AES stets geringere Gesamtkonzentrationen im Ablauf gemessen: Die mittlere AES-Gesamtkonzentration in den Abläufen betrug 0,57 Mikro g/L. Zwischen den Gesamtkonzentrationen von AES und LAS bestand keine Korrelation. In den Zuläufen beprobter Kläranlagen wurden im Mittel 3.200 Mikro g/L LAS detektiert. Damit betrug die mittlere Entfernung für LAS 99,6 %. Die mittlere AES-Konzentration im Kläranlagenzulauf belief sich auf 680 Mikro g/L, was einer mittleren AES-Entfernung von größer als 99.9% entspricht. Retrospektives Screening von 1.564 Tensiden und deren Transformationsprodukte (TPs) erfolgte durch ein zweites Labor unter Anwendung der Ultrahochleistungsflüssigkeitschromatographie mit Flugzeitmassenspektrometer-Kopplung (UHPLC-QTOF-MS). In vielen Fällen wurde die Konzentration von LAS von der Summe der Konzentrationen der Neben- und Transformationsprodukte von LAS überstiegen. Für die LAS-Nebenprodukte Dialkyltetralinsulfonate (DATS) lag die maximale Summenkonzentration bei 19 Mikro g/L, für die Sulfophenylalkylcarbonsäuren (SPACs) bei 17 Mikro g/L und für die Sulfotetralinalkylcarbonsäuren (STACs) bei 5,3 Mikro g/L. Hohe Konzentrationen von bis zu 7,4 Ìg/L wurden für Polyethylenoglycole in den Abwasserproben bestimmt. Die Gesamtkonzentration aller quantifizierten Tenside, TPs und Nebenprodukte in einer einzelnen Probe betrug bis zu 82 Mikro g/L.

Infra-red thermometry in alpine terrain

Rough mountain terrain offers climatic conditions (niches) to plants and animals poorly Represented by conventional climate station data. However, the extent to which actual Temperatures deviate from those of the freely circulating atmosphere had never been assessed At a landscape level. Here, we quantify thermal life conditions across topographically rich Mountain terrain by using a combination of thermal (IR) imagery of surface temperature with Data from a large number of miniature data loggers buried at 3 cm soil depth. The data Obtained from six alpine (Alps) and arctic-alpine slopes (Norway, Sweden, Svalbard) evidence Persistent root zone temperatures of 2-4K above air temperature during summer. Surface Temperatures show strong positive (2-9 K) and negative (3-8 K) deviations from air temperature On bright days and clear nights, respectively. As to be expected, south oriented slopes are Warmer than west and north slopes but microclimatic variation on clear sky days was strong Within all slopes, with 8.4 2.5K (mean SD) surface temperature differences persisting over Several hours per day along horizontal (i.e., equal elevation) transects. Life conditions of Alpine organisms are thus strongly decoupled from conditions in the free atmosphere and Cannot reliably be inferred from climate station data in both, temperate and arctic latitudes. Microtopography can mimic temperature differences of large elevational (or latitudinal) Gradients over very short horizontal distances. This is important in the context of climate Change because it shows that species do not necessarily need to climb several hundred meters In elevation to escape the warmth. Quite often, few meters of horizontal shift will do. For Plants unable to, or too slow to adapt to a warmer climate, thermal microhabitat mosaics offer Both refuge habitats as well as stepping stones as atmospheric temperatures rise.

STOHBAU 2012-2013: Erweiterte Zulassung,Qualitätssicherung und Strohbaurichtlinie - Erweiterung der bestehenden Zulassung,Optimierung von Herstellung und Qualitätssicherung, Erstellung einer Strohbaurichtlinie

Mit dem bei der FNR eingereichten Vorhaben will der 'Fachverband Strohballenbau Deutschland e.V.' (FASBA) für die Strohbauweise in Deutschland einen klaren Bezugsrahmen für die Anwender erarbeiten. Das Bauen mit Stroh soll eine attraktive, wählbare und technisch sichere Alternative zu herkömmlichen Bauweisen werden. Das Vorhaben ist in zwei Arbeitspakete untergliedert. Zum einen soll die bestehende allgemeine bauaufsichtliche Zulassung so erweitert werden, dass die Vermarktungsfähigkeit der Bauweise verbessert und der Anwendungsbereich dieses nachwachsenden Rohstoffes durch eine direktverputzte Bauweise deutlich erweitert werden kann. Die Optimierung des Herstellungsprozesses und der Qualitätssicherung wird als Voraussetzung für die Erweiterung der Zulassung dienen. Zum anderen soll die Ausarbeitung einer Strohbaurichtlinie die fachgerechte Umsetzung in der Fläche ermöglichen und die Grundlage einer fachgerechten Ausbildung bilden. Im Ergebnis wird sich die Vermarktbarkeit dieser Bauweise erheblich verbessern und sie wird das Rückgrat der Akteure stärken.

Challenges in luminescence dating applications of quartz

Luminescence dating methods using quartz may suffer from i) incomplete optical resetting (bleaching) of the latent signal at deposition, ii) limited saturation dose and,thus, limited time range using UV-A or blue emissions. The project objectives first consists in exploring and separating OSL emissions from quartz of different sensitivity to light and to isolate components suited for specific dating applications with the Linear Modulation technique. Rapid environmental change with or without human impact will be dated more precisely and more reliably using this sophisticated technique. Secondly it is tried to extend the upper dating limit by using orange-red TL emissions (RTL) from quartz extracted from heated samples (e.g., crustal xenoliths from volcanic eruptions) and from sediments which are too old for conventional OSL dating. Both approaches require fundamental research into the luminescence characteristics of (dose-saturated) quartz crystals from different geological origin (granitic, hydrothermal, sedimentary). Objectives in order: 1. Sampling and refining pure quartz from different geological and petrographic environments and from a well-studied last glacial loess section (Nussloch). 2. Investigating basic luminescence characteristics from different quartz of different origin, with focus on OSL components (LM-OSL) and red TL emissions (RTL). 3. Testing improved techniques (LM-OSL) to recognize incomplete or inhomogeneous signal resetting at deposition and to precisely determine the true burial dose. 4. Extending the upper limit of luminescence dating through use of RTL emissions from heated and from sedimentary quartz. 5. Improving and ensuring of dose rate calculations using different low-level methods including modeling of disequilibrium and spatial non-homogeneity if applicable. 6. Comparing dating results from loess with independent chronologies and other high resolution records of rapid climate change.

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